The minimization of uncertainty with regard to data is universally held as advantageous. Moreover, and fundamentally, in as much as there exists a premium on precision in acquiring data, to appreciate and acknowledge uncertainty with regard to data acquisition is likewise of value so that “meaningful” data informs the technician, clinician, scientist, engineer, etc.
Fluorescence photometry is premised upon the adsorption and subsequent re-radiation of light, i.e., electromagnetic radiation, by organic and inorganic specimens. Via fluorescence labeling or tagging of a specimen, sample, etc. with a fluorophore (a/k/a, a fluorochrome), i.e., a functional group of a molecule which absorbs energy of a specific wavelength and re-emits energy at a different, but equally specific wavelength wherein the amount and wavelength of the emitted energy depend on both the fluorophore and the chemical environment of the fluorophore; the application of excitation energy to such specimen; and, monitoring or sensing of emission energy from the excited specimen, the presence/absence and/or quantity of a tagged component of the specimen may be obtained or ascertained. Well known illustrative, non-limiting fluorescence photometry fields include, molecular biology, biochemistry, and pharmaceutical science, with particular, but hardly exclusive utility known with regard to genotyping, sequencing, screening and clinicals.
Characteristic of scanning operations is a scanner, a target, and motion of one element with respect to the other. Upon reflection, it should be appreciated that potential scanning issues arise in connection to the inherent motion of scanning, e.g., getting either the scanner or the target from point A to point B, as well as the relative positioning or alignment from one target to the next for the purpose of data acquisition.
Optical scanning heads, more particularly photometers, include components, such as photomultiplier tubes (PMTs), which are susceptible to mechanical vibration. One cause of mechanical vibration is the physical quantity known as “jerk” (J), mathematically the first time-derivative of acceleration (A), i.e., J=dA/dt, which is manifest or inherent in the motion cycle of a scanning carriage to which a scanning photometer is commonly attached. In an effort to eliminate jerk related vibration in or with respect to the photometer, it has heretofore been found advantageous to provide a static or stationary photometer, and a dynamic specimen medium, e.g., a selectively positionable plate, which passes thereby. With increased processing throughput via the use of continuously spooled array tape and the like, use of a stationary photometer has become impractical, however, any inconsistency in the relative position between the scanning photometer and each target of a series of targets, due to any reason, can cause significant differences in the quality of output data.
In the context of a multi-dye fluorescence assessment, the characteristic multiple fluorophore excitation energy directed to a first target, and returned fluorophore emission energy from the excited target, e.g., the paths associated therewith, must be precise, certain and repeatable/reliable in relation to the target itself, as well as from a first target to successive targets. Repeatability of data acquisition conditions is highly valued, and in the context of reduced specimen/target volumes for scanning, and with regard to the high volume throughput available with array tapes, repeatability, reliability and precision is an increasing challenge. Thus, in light of at least the forgoing, it remains advantageous to provide a scanning photometer capable of precise, reliable and repeatable data acquisition, more particularly, such scanning photometer and associated methods which complement heretofore known target media processing advancements.